Earthquake leads direct or indirect damages to national economic construction and peoples' life and property. It is meaningful to use an efficient relief device to save millions of peoples' life. Compared with current earthquake relief and rescue approaches, hydraulic pincer and rock grabbing devices play an important role in a forcible entry process during earthquake relief by implementing multi-purposes in a single device. This is very meaningful for earthquake relief and economic construction after the earthquake. Current rescue multi-purpose devices usually use arm structures; a single mechanical arm is installed with a single accessory. The method has some problems such as inconvenient operation, difficult to manufacture and high investment. Accordingly, a new combining way of accessories is need such that multiple functions may be simply implemented by a device.